Automatic water heater



June 16, 1936. I W. HODGES l AUTOMATIC WATER HEATER Filed April ll, 1952 2 Sheets-Sheet l OUTLET INLET June 16, 1936. L, W, HODGES 2,044,611

l AUTOMATIC WATER HEATER Filed April-11, 1932 2 sheets-sheet 2 CURRENT Sl/PLY WA TER SUPPLY I 44 www: f

We/77W Patented June 16, 1936 UNITE STATES resi orgies AUTOMATIC WATER, HEATER poration of Ohio Application April 11,

4 Claims.

One object of my invention is to provide an automatic water heater which is compact, self-contained, durable and inexpensive.

A further object is to provide a water heater employing electric current for heating the Water with thermostatic means for controlling the operation of the heater and thereby controlling the temperature of the water discharged therefrom.

A further object is to provide an electric water heater which is eificient because it is made in the form of an individual unit to be positioned closely adjacent the faucet from which the hot water is discharged so as to eliminate all heat losses in hot water pipe lines such as experienced in present day water heaters which are designed to supply several different, widely spaced, hot water faucets, thus requiring long pipe lines from which the heat of the water therein is radiated and thus lost.

A further object is to provide a water heater for water which can be made in the form of an individual unit and can be placed adjacent a hot water faucet so that as soon as the faucet is opened, hot water will start discharging therefrom.

Another object is to provide a hot water heater of such construction that the formation of scale is eliminated and the heating element is so designed and arranged with respect to a receptacle in which the water is heated that the heat of the heating element caused by energization thereof is immediately absorbed by the water in the receptacle, thus keeping the heating element below a glowing state and hence insuring an indefinite life therefor.

A further object is to provide a receptacle with a plurality of heating elements associated therewith for warming the contents of the receptacle and to provide a multiple switch for progressively energizing and deenergizing the heating elements, the switch being automatically operated, dependent upon temperature changes of the water within the receptacle.

Still a further object is to pro-vide a receptacle which is porcelain enameled inside and out, to

discourage the deposit of scale thereon, and to provide a heating element associated therewith, a coating of insulation being provided on the enameled exterior of the receptacle, the heating element being embedded in the insulation.

vto atmosphere.

1932, Serial No. 604,557

(Cl. 21S-39) Still another object is to provide a novel thermostatic switch for controlling the operation of the heater, with novel adjusting features for the switch.

With these and other objects in View my invention consists in the construction, arrangement and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings, in which:-

Figure 1 is a perspective View of a lavatory with a hot water heater embodying my invention connected therewith.

Figure 2 is a perspective view of the hot water 15 heater itself, parts being broken away and other parts being shown in section to illustrate the details of construction of the heater.

Figure 3 is a vertical sectional view through an, automatic switch of the multiple type used on my hot water heater. Y

Figure 4 is a sectional view on the line 4-4 of Figure 3.

Figure 5 is a side elevation, partly in section, of the receptacle and heating element during one stage of the process of making the heater.

Figure 6 is an enlarged sectional View of the portion of Figure 5 shown in the circle 6.

Figure '7 is an end elevation of the multiple switch shown in Figure 3.

Figure 8 is a sectional View on the line 8-8 of Figure 3.

Figure 9 is a plan View of a modified form of switch showing snap acting mechanism associated therewith.

Figure 10 is aside elevation of the switch shown in Figure 9.

Figure 11 is a diagrammatic view of the switch shown in Figure 9.

Figure 12 is a diagrammatic view of a multiple switch and a plurality of heating elements electrically connected therewith; and

Figure 13 is a diagrammatic View of my heater showing it connected with a hot water faucet for a laundry tub.

On the accompanying drawings I have used the reference numeral i@ to indicate a receptacle or tank made of steel or the like. A cold water inlet pipe l2 and a hot water outlet pipe lil are screw threadedly associated with the tank Ill. The pipes l2 and M are then welded as indicated at I6 (see Figure 6) to insure permanent non-leak assembly of the parts Il), I 2 and I4 relative to each other. The entire tank I0 and pipes I2 and I4 are then coated both inside and outside with a porcelain enamel coating I3.

The tank i@ is provided with a boss Ztl, the purpose of which will hereinafter be described. vAfter the tank is enameled, it is covered with plastic insulating material 22 after which one or more looped heating elements 24 are wound thereon. Additional plastic insulation 22 is then used to cover the heating element 2Q so as to properly space the element from the tank lil and insulate the outside of the element against short circuit or damage from anything touching the exterior of the tank when completed. The insulating material 22 may be a clay-like substance or refractory heat conducting cement, but should be a good electric insulator so that it will prevent short circuit between the coils of the heating element.

It will be noted that the heating element or elements are distributed to cover at least the major portion of the tank so that when the heating element is energized there is a d'enite area of the tank from which the water within the tank can absorb heat as transmitted to the tank from the heating element. The heating element is separated from the tank by only a coating of the refractory cement 22 so that the path of heat transmission is short and the results obtained by actual experiment have been to quickly heat the water and prevent the heating element from being heated to a glowing condition. Obviously this makes the heating element practically indestructible, inasmuch as red or white heat of heating elements is the'main cause of their eventual destruction.

As a further destruction preventative, I also provide a thermostat switch which automatically prevents the heating element from attaining more than a predetermined temperature as will hereidnafter be described.

I provide the heating elements in looped formation so that the electro-magnetic effect of onehalf of any given loop counteracts the electromagnetic elect of the other half and thus produces a non-magnetic heating element which avoids the possibility of the tank it acting as the secondary of a transformerY and the heating element as the primary, thus inducing'hea'vy electric current in the tank, which would be wasteful of electric energy and detrimental to the tank itself.

My hot water heater can be made in several capacities such as a half, one, two and one half and five gallon sizes, to suit different purposes. A half gallon size, for instance, is quite suitable for a bathroom lavatory, while a two and one half gallon size is suitable for a laundry room. The ve gallon size is suitable for connection with abath tub. It will be obvious, of course, that heaters of other capacities can be built.

One of the important features of my invention is the provision of a small self-contained heater which can be located closely adjacent the faucet from which hot water is to be discharged. The heater, being small, is therefore adaptable for individual installation without excessive expense. great efficiency is obtained by the particular arrangement of the heating element as above described and additional efficiency over a central heater tank for several faucets is obtained by the 1 extremely short pipe line from the heater to the hot water faucet.

For instance, I have shown in Figure 1 a short pipe 26 extending from the outlet 'M to the hot water faucet 28 of the lavatory 3Q; The tank li! which is encased in a casing 32 may be mounted in the wall behind the lavatory, or directly underneath the lavatory, if desired. As shown in Figure 13, it can be mounted above a laundry tub 34 so that the hot water pipe 35 to the hot water faucet 38 is but a comparatively short pipe.

Further enciency is secured by providing the casing 32 of larger dimensions than the completed heater and filling the intermediate space with insulation fill to prevent the transmission of heat from the heater to the exterior atmosphere.

In the boss 2Q I screw a fitting 42 having a switch mounted thereon. The switch comprises a support IM of insulating material with one or more pairs of contact springs 46 mounted thereon.' The contact springs ll are U-shaped, having long and short legs as illustrated in Figures 8 and 9 with contacts i8 carried by the contact springs. Screws 5@ serve to secure the springs 4S to the insulating support 1M. The contacts 48 are normallyengaged with each other.

The support M is mounted on a plate 52 which is rotatably mounted on the upper end of a threaded stud 54 extending from the tting 42. A second plate 5G is mounted on the stud 54 and retained in a predetermined position relative `to the fitting l2 by a nut 5B.

The plate 52 is slotted as indicated at Si) in Figure 4 and is thereby adjustable relative to the plate 56, a screw E2 being provided to retain the adjustment.

An actuator 54 is provided for the Contact springs 4E and consists of a rotatable rod having flattened portions 66 between the pairs of contact springs. springs as indicated in Figures 2 and 10, there is only one flat spot 55. Where there are a plurality of the lflat spots, the upper end of the actuator 64 is rotatably supported by a screw 68 extending through an arm 'i9 which has one end anchored to the support M. the actuator has the upper end of an actuating rod 72 embedded therein. The rod l2 rotatably extends through the fitting 42 and has the'upper end of a bimetallic temperature responsive coil 14 screwed thereto. lIhe lower end of the coil 14 extends through a cap l5 on the lower end of a tube 78, and is soldered or otherwise secured thereto. The 'upper end of the tube 'i8 has its end soldered or otherwise secured to the lower end of the fitting 52.

From the construction of the parts just described, it will be obvious that the tube I8 extends within the tank it and the temperature of the water therein will aifect the temperature within the tube i8 and thereby aiect the coil 'M to twist or untwist it in proportion to the temperature of the water. This will automatically rotate the actuator 6d so that the at spots thereon Will turn toward a crosswise position between the contact springs and separate them and thereby separate the contacts 48 for de-energizing the heating elements automatically. Where but one heating element is provided the single switch de-energizes it when the temperature of the water reaches a predetermined degree at which the switch is set. The setting can be changed by adjusting the plate 52 relative to the plate 5t or by adjusting the contact springs 16 as will hereinafter appear.

Where there are a plurality of heating elements such as three, as illustrated in Figures 5 and l2, the settings for the three switches are different so that the heating elements are energized and de-energized progressively, this being Where there is only one pair ofl rlhev lower end of illustrated in FigureV '7 in which the upper contacts are first disengaged, then the middle ones and lastly the lower ones. The upper ones can be disengaged before the water reaches the degree predetermined while the lower ones can be disengaged at the predetermined degree.

As shown in Figure 8 adjusting screws 89 may be provided for drawing the contact springs toward the support 4l! and thereby rocking the short leg portions dta of the springs with the contacts 48 as pivots. This spreads the portions 46a (the lower ones being spread more than the upper ones in Figure 8) so that the lower ones will be separated later than the upper ones, as the actuator Sli rotates.

On the single switch, the adjusting screws can be tightened for delaying the opening of the contacts 48 and thereby automatically opening the switch when the water reaches a higher temperature than when the screws 80 are adjusted looser.

As shown in Figure 4, I provide a stop lug 82 on the plate 52 for a stop lever 84 to engage when the switch is in off position. The lever 84 is part of a washer 8S which is non-rotatable relative to the actuating rod 12.

Snap action can be provided for the switch so that the contacts 48 will snap apart rather than being moved apart slowly. In Figures 9 and 10 I show a snap action spring 88 having a V-portion 9D for a lug 52 of a hub 94 to engage. The hub 94 rotates with the actuator 64 and when the lug 92 reaches the dotted line position in Figure 9, it is just on the peak of the v-portion of the spring S8. In this position the edges of the flat spots 66 are just ready to engage the contact springs and upon slight additional rotation of the lug 32 it will cross center, whereupon the spring 88 springs inwardly and quickly rotates the hub 94 in the direction of the arrow a in Figure ll to the position shown in this figure. This quickly separates the contacts with a snap action to prevent arcing between the contacts.

I have shown how the switch can be adjusted for predetermined water temperatures and might mention that at the factory the switch can be set for opening at degrees, but by shifting the plate 52 relative to the plate 56, higher or lower temperatures may be automatically produced for the water in the heater. I have shown the thermostatic switch installed in the top of the tank IS, this being preferable, at least in the smaller sizes of tanks, so that there will be no interference with the refractory cement 22 covering the tank.

While the switch shown in Figure 3 is designed for controlling three heating elements it is apparent that it may be formed to control any plurality of heating elements, or to control just one as shown in Figure 2.

The refractory cement 22 has the qualities of insulating the heating elements embedded therein and of conducting heat.

The process involved in applying the heating elements to the tank is as follows:

First-the porcelain enamel coating is applied at a high temperature, such as l600 Fahrenheit. Secondthe tank is dipped into the refractory cement while the cement is in a plastic or semifluid condition and then baked. Thirdthe element wire or wires are wound over the rst coat of refractory cement. Fourth-the tanks are again dipped into the plastic refractory cement, thus coating the outside of the heating elements and this coating is then baked. Fifth-the waterproongmaterial is then brushed or sprayed on the completed tank and allowed to air-dry. rIhe combination of enameled tank, refractory embedded heating element distributed over the major portion of the tank and efficient insulation of the tank, together with a short hot water travel from the tank to the hot water faucet produces an electrically operated instantaneous hot water heater which is fully as economical as any hot water heater which serves several faucets and burns gas, oil or other fuel. Being electrically operated, the hot water heater is entirely fool proof and automatic and when once installed, requires no further attention.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim as my invention:-

1. In an automatic water heater, a water tank, an inlet pipe connected with the bottom thereof,

an outlet pipe connected with the top thereof, at l* least said outlet pipe extending horizontally from said tank, a heating element wound on said tank to heat the contents thereof when said heating element is energized, a thermostatic controller for said heating element extending downwardly into said tank from the top wall thereof, said thermostatic controller comprising a threaded f1tting, a casing in water tight connection with said threaded tting and -depending therefrom, a temperature responsive element within said casing, and a switch connected therewith for operation thereby and electrically connected in circuit with said heating element, the top wall of said tank having a threaded boss for reception of said tting.

2. In an automatic water heater, a water tank, an inlet pipe connected with the bottom thereof, an outlet pipe connected with the top thereof, at least said outlet pipe extending horizontally from said tank, a heating element wound on said tank to heat the contents thereof when said heating element is energized, a thermostatic controller for said heating element extending downwardly into said tank from the top Wall thereof, said thermostatic controller comprising a fitting, a r

casing in water tight connection with said fitting and depending therefrom, a temperature responsive element within said casing, and a switch connected therewith for operation thereby and electrically connected in circuit with said heating element, the top wall of said tank having a boss for reception of said fitting, a casing surrounding and spaced from said tank, insulating material interposed between said heating element and said casing, said switch being located outside of said fitting and said insulation, and a cover for said casing adjacent said switch.

3. In an automatic water heater, a water tank, an inlet pipe connected with the bottom thereof, an outlet pipe connected with the top thereof, a heating element for said tank to heat the contents thereof when said heating element is energized, a thermostatic controller for said heating element extending into said tank, said thermostatic controller comprising a threaded fitting, a casing in water-tight connection with said threaded fitting, and extending therefrom, a temperature responsive element within said casing and a switch connected therewith for operation thereby and electrically connected in circuit with 75 perature responsive velement within sai-d casing, and a switch connected therewith for operation thereby and electrically connected in circuit with said heating element, said wall of said tank having a boss for reception of such fitting, a casing surrounding and spaced from said tank, insulating material interposed between said heating element and said casing, said switch being located outside of said fitting and said insulation and a cover for said casing adjacent said switch.

LEE WALLIS HODGES. 

